• Journal of the Korean Chemical Society
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• v.38 no.4
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• pp.309-318
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• 1994

The stable defect structure and the single phase region of La$_2O_3$-modified BaTi$O_3$ have been studied by X-ray diffractometer and scanning electron microscope. The stable defect structure of La$_2O_3$-modified BaTi$O_3$ has been identified as [($Ba^x_{Ba})_{1-2x}(La{\cdot}_{Ba})_{2x}][Ti^x_{Ti})_{1-x/2}(V""_{Ti})_{x/2}]O_3$ which consists of La$^{3+}$ ion substitution for Ba$^{3+}$ ion in the lattice structure and the formation of Ti vacancies for the charge compensation. When 3 mol% of La$_2O_3{\cdot}3/2TiO_3$ was added to BaTi$O_3$, the unit cell structure was transformed from tetragonal to cubic and the solubility limit was about 14 mol%. When La$_2O_3{\cdot}3/2TiO_2$ was added above this solubility limit, the second phase, La$_4Ba_2Ti_5O_{18}$, was formed. In the La$_2O_3$-modified BaTi$O_3$, it was found by the liquid phase sintering process that the sinterability was decreased by excess BaO but increased by excess Ti$O_2$.

• Korean Journal of Materials Research
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• v.10 no.7
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• pp.478-481
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• 2000

Single phase $Pb(Mg_{1/3}Nb_{2/3})O_3$ ceramics doped by 10 mol% of electron donors such as $La^3,\; Pr^{3+,4+},\; Nd^{3+},\; Sm^{3+}$, were synthesized and their B-site cationic ordering structures were investigated by XRD and TEM. In the XRD patterns, only fundamental reflections were observed for the undoped $Pb(Mg_{1/3}Nb_{2/3})O_3$, while the (h/2 $\textsc{k}$/2ι/2)(h,$\textsc{k}$,ι all odd) superlattice reflections resulting from the 1:1 ordering induced unit cell doubling were also observed for the donor-doped $Pb(Mg_{1/3}Nb_{2/3})O_3$. In the TEM selected area diffraction patterns, the (h/2 k/2 l/2)(h,k,l all odd) superlattice reflection spots as well as the fundamental reflection spots were observed for all the samples, but the relative intensities of the superlattice reflection spots to the fundamental reflection spots were significantly enhanced by the donor-doping. In the TEM dark-field images, antiphase boundaries were observed only for the donor-doped $Pb(Mg_{1/3}Nb_{2/3})O_3$. It was therefore experimentally verified that doping by electron donors such as $La^3,\; Pr^{3+,4+},\; Nd^{3+},\; Sm^{3+}$, enhances the B-site cationic 1:1 ordering in $Pb(Mg_{1/3}Nb_{2/3})O_3$. These experimental results were interpreted in terms of the charge compensation mechanism.

• The Korean Society of Law and Medicine
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• v.12 no.1
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• pp.177-225
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• 2011

Verdicts related to major medical litigation given by the Seoul Central District Court, the Seoul High Court and the Supreme Court in 2010 were analyzed. It's shown that in cases of the medical negligence regarding the occurrence of neonatal cerebral palsy, the plaintiff claims were dismissed using criteria proposed by associations of Obstetrics and Gynecology and Pediatrics in US, and thereof the burden of plaintiffs to prove the medical negligence has increased. In addition, in case of that the expected survival period of infants gets longer, payments for treatment and nursing after survival period determined by judges are made and it was judged to compensate it as a periodical indemnity. In case for the explanation obligation the most frequently mentioned in the medical litigation, in addition to cases of invoking the existing theory of explanation obligation, verdicts to mention the instructions of theory regarding instruction explanation obligation and the possibility of compensation for damages on property are given. Particularly, in cases for a liability of reparation by exaggerating the effects and not disclosing the risks related to treatment with stem cells, even if the treatment not approved by Food and Drug Administration is in violation of the Pharmaceutical Affairs Law, it's not illegal as violation in Pharmaceutical Affairs Law itself. But there is a certain verdict to present the possibility of an extension of the theory of explanation obligation by acknowledging the liability of reparation caused by illegal acts with no explanations of effects and risks of treatment with stem cell by doctors and pharmaceutical companies. In an incident in which a mental patient fell and died through the opened door of the roof at the hospital, a liability of reparation was acknowledged due to defects in structure installation management and this verdict drew an attention since the overall management responsibility about patients including structures was acknowledged to the hospital besides the obligations on medical practice. In case of the verdict without giving the opportunity to state the opinion with respect to the main legal issues, the responsibility of the court was emphasized since the court did not fulfill the explanation obligations. There were some cases in which payments for nursing and caring to a patient in vegetative state during the plastic surgery was admitted. However, in dental-related incidents, the proportion of cases in which plaintiff won was low since the difficulty of proving may be reflected. In the area of administrative litigation, unlike the existing position regarding arbitrary medical charge cover collected from patients in hospital, the verdict to admit the legitimacy of collection of medical treatment was given and attracted the attention of people. Verdict in which the expression related to medical advertisement was not exaggerated disposed the original verdict and pointed out the problem of excessive regulations on medical advertisement. The effort to analyze the trend of verdicts of court through reviewing the decisions and to organize should be continued, but the full decision should be disclosed as a base, and people and systems to enable the all time monitoring should be prepared.

• Journal of the Korean Chemical Society
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• v.38 no.8
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• pp.539-546
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• 1994

The critical micelle concentration(CMC) and the counterion binding $constant(\beta)$ at the CMC of cetyltrimethylammonium bromide(CTAB) in a series of aqueous solutions containing medium chain-length n-alcohols(Propanol, Butanol, Pentanol and Hexanol) have been determined from the concentration dependence of electrical conductance at serveral temperature from $17^{\circ}C\;to\;41^{\circ}C.$ Thermodynamic parameters $({\Delta}G^o_m,\;{\Delta}H^o_m,\;{\Delta}S^o_m,\;and\;{\Delta}C_p)$ associated with micelle formation of CTAB have been also estimated from the temperature dependence of CMC and $\beta$ values, and the significance of these parameters and their relation to the theory of micelle formation have been considered. The results show that an enthalpy-entropy compensation effect is usually observed for the micellization of CTAB. The effects of n-alcohols on the micellar properties (CMC and $\beta$) of CTAB solutions have been also investigated. The addition of n-alcohol to the CTAB solution in a small quantity decreases the CMC value and the counterion binding constant $(\beta)$ at the CMC, but the addition of n-alcohol in an excessive quantity increases the CMC values on the conterary. These results have been explained in terms of the effect of the micelle-solubilized alcohol on the micellar surface charge density.

• The Journal of the Korean dental association
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• v.48 no.4
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• pp.280-287
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• 2010

Objective: In spite of increasing dental treatment for the disabled, there was a few collected data on dental treatment status and dentists' perception in Korea. The purpose of this' study is to research the current dental treatment status for the disabled in Korea and to suggest public health policies for the disabled. Material and methods: Total of 68 dentists who have treated the disabled regularly were asked to fill questionnaires regarding dental treatments for the disabled. Results: 1. It is necessary to set up public dental center for the disabled in rural area. 2. In case of dental treatments relating to cerebral palsy, ADHD, autism, the compensation for treatment time and extra investment is needed. 3. Only 39.7% of dentists charged treatment fees to the disabled as same as normal patients. Moreover 38.2% of dentists answered that they didn't charge treatment fees at all when their patient are disabled. 4.23.5% of dentists provided all of dental treatments including dental implant and orthodontic appliances in Korea. However, 54.3% of dentists reported the improvement of access to dental implant, orthodontic and esthetic treatment is needed. 5. It is imperative for the government to improve the support system for the disabled. Conclusions: Through this research only 26.5% of dentists answered that they had received the fund from the government and 11.1% of them were satisfied with the support for the disabled in Korea. This indicated the improvement of government financial support system for the disabled is needed.

• Journal of Preventive Medicine and Public Health
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• v.30 no.2 s.57
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• pp.293-307
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• 1997

In Korea, sudden deaths of middle-aged and older male workers who are the responsible persons at home as well as workplace, have aroused social concern. Besides, U. N. has reported recently that mortality of Korea male in 40-50's was one of the highest among newly developed countries in 1992. Not much is, however, known about the nature of the work contributing to the mortality of different groups of workers. Therefore, this study was done to examine mortality of public servants, comprising about 5% of all the employed in Korea, according to their job titles and grades. The datas of 1753 official deaths, comprised 323 (only disease-oriented deaths) applicants of survivors' compensation, were used to examine age-adjusted Standardized Mortality Ratios(SMRs) according to their job titles, grades, tenures and cause of deaths. Controlling age and sex difference was conducted using 26,950,481 general population, 95,340 general deaths and 864,560 working public servants. All the groups were aged 20-64, who were being observed January - December in 1993, at the same time. Results and discussions are as follows. 1. SMRs standardized by general population was significantly low (SMR 44.9 CI 42.8-52.7) for all job titlses. Of public servants, 90.0% was graduated from high school, although 17.5% in general population. The distinction of social status such a education may produce a strong healthy worker effect. Besides, SMRs for different tenure groups showed a steady increase as tenure increases. This suggests that the magnitude of healthy-worker effect may be greater with increasing tenures. 2. SMRs standardized by own public servants was significantly elevated for work-men(SMR 121.0, CI 110.2-132.6) in solitue. When SMRs for different grade, of work-men was examined, 9th(SMR 124.2, CI 104.4-146.7) and 10th(SMR 137.9 CI 120.8-156.8)grade, lower grade in workmen, showed significantly elevated SMRs. Of workmen, 57.0% were graduated from high school and 50.1% in 9th grade, as well. These mean that low economic states made up social class, education may increase mortality rate. 3. Of SMRs according to all causes of death, only policemen on 'cause of death related hypertensive disease'(SMR 282.5, CI 121.6-556.7) was significantly high except for' cause of death related other signs, symptoms and ill-defined conditions'. 4. When SMRs on cause of death related hypertensive disease for different grade of policemen was examined, senior policemen(SMR 241.9), in charge of the front service, showed elevated SMR, in spite of statistical no significance. Especially, the working hour of senior policemen is quite long and also the work schedule is even more irregular for policemen. The results of this study showed that mortality for different jobs differed, and it differed also for different grades in the same job. This difference in mortality may reflect the difference in the nature of job contents, and further studies are warranted to elucidate which job characteristics are responsible.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.10
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• pp.805-810
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• 2012

Transparent conducting oxides (TCOs) have wide range of application areas in transparent electrode for display devices, Transparent coating for solar energy heat mirrors, and electromagnetic wave shield. $SnO_2$ is intrinsically an n-type semiconductor due to oxygen deficiencies and has a high energy-band gap more than 3.5 eV. It is known as a transparent conducting oxide because of its low resistivity of $10^{-3}{\Omega}{\cdot}cm$ and high transmittance over 90% in visible region. In this study, co-doping effects of Al and Y on the properties of $SnO_2$ were investigated. The addition of Y in $SnO_2$ was tried to create oxygen vacancies that increase the diffusivity of oxygen ions for the densification of $SnO_2$. The addition of Al was expected to increase the electron concentration. Once, we observed solubility limit of $SnO_2$ single-doped with Al and Y. $\{(x/2)Al_2O_3+(x/2)Y_2O_3\}-SnO_2$ was used for the source of Al and Y to prevent the evaporation of $Al_2O_3$ and for the charge compensation. And we observed the valence changes of aluminium oxide because generally reported of valence changes of aluminium oxide in Tin - Aluminium binary system. The electrical properties, solubility limit, densification and microstructure of $SnO_2$ co-doped with Al and Y will be discussed.

• Korean Security Journal
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• no.16
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• pp.321-338
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• 2008

Soongrae-Mun Fire shows safety problem in Korea intimately. People have pressed for the responsibility of persons in charge and have asked for improvement measure whenever Fire accident occur, but similar accidents occur again without any improvement. This research is to provide improvement. measure on the base of the analysis of the cause of Soongrae-Mun fire to prevent similar accident, also to help private security company do effective security job. This research is approached from a security point of view. A lot of accidents occur by direct cause such as people's unsafe action and unsafe condition. but it is very difficult to remove the facts of direct cause, so the facts of indirect cause should be analyzed together. Drew-up of security related legislation should be included when the establishment of fire fighting related legislation is examined, also technical improvement should be examined with legislation. security company should be concerned about securing of expertise and reinvestment for the improvement of expertise to overcome limitations of private security such as job boundary, capability and responsibility. Also private security company should try to service for public benefit and to examine practical compensation for loss occurred by mistake of security company.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.111-120
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• 2019

This study examined the mediating effects of perceived organizational support (POS) on the relationship between the person-job fit and job satisfaction of service workers. POS is divided into socioemotional POS and instrumental POS. To achieve the research purpose, a questionnaire survey was conducted on workers in charge of service jobs in domestic companies through an on-line survey system and finally, the results of 281 respondents were analyzed to verify the hypothesized research model with an 80.3% effective recovery rate. The findings are as follows. First, the person-job fit has positive effects on job satisfaction and POS. Second, among the sub-constructs of POS, socioemotional support has mediating effects, but instrumental support has no mediating effects on the relationship between person-job fit and job satisfaction. Based on the results of this study, this study suggests theoretical and practical implications for the human resource development and management of service workers. Overall, changes in the recruitment system, which can judge the person-job fit of employees who perform emotional labor facing customers, organizational culture and personnel system for establishing socioemotional support system, and compensation and workforce development system, are needed to enhance the job satisfaction of service workers.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.2
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• pp.309-316
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• 2019

In this paper, a low-jitter delay-locked loop that compensates for local clock skew is presented. The proposed DLL consists of a phase splitter, a phase detector(PD), a charge pump, a bias generator, a voltage-controlled delay line(VCDL), and a level converter. The VCDL uses self-biased delay cells using current mode logic(CML) to have insensitive characteristics to temperature and supply noises. The phase splitter generates two reference clocks which are used as the differential inputs of the VCDL. The PD uses the only single clock from the phase splitter because the PD in the proposed circuit uses CMOS logic that consumes less power compared to CML. Therefore, the output of the VCDL is also converted to the rail-to-rail signal by the level converter for the PD as well as the local clock distribution circuit. The proposed circuit has been designed with a $0.13-{\mu}m$ CMOS process. A global CLK with a frequency of 1-GHz is externally applied to the circuit. As a result, after about 19 cycles, the proposed DLL is locked at a point that the control voltage is 597.83mV with the jitter of 1.05ps.